It is well known to employ pipe clamps to secure elongate articles, such as pipes, conduits and the like to structural channels. Structural channels are generally U-shaped members having upper ends including inwardly turned flanges, which support thereacross pipes or other elongated articles. The pipe clamp, which is typically a two piece member, is positioned over the pipe and secured to the channel around the pipe to support the pipe to the structural member. A fastener such as a bolt secures the two pieces together.
Typically pipe clamps of this type include a pair of straps which are identical. Each strap includes an attachment portion which includes hook-like feet which engage the inwardly turned flanges of the U-shaped channel, an intermediate portion for wrapping around the pipe and a connection portion extending outwardly therefrom. The connection portion extends upwardly beyond the pipe and includes aligned apertures therethrough. The apertures accommodate a fastening member, such as a threaded bolt, which may be threadingly secured therethrough to tighten the straps around the pipe thereby securing the pipe to the structural channel.
One example of a pipe clamp of this type is shown in U.S. Pat. No. 3,547,385. As may be appreciated, the pipe clamp must support the pipe to the structural channel in a fashion where a load placed on the pipe will not dislodge the pipe from the structural channel. The particular design of conventional pipes clamps serves adequately to secure the pipe to the channel, inasmuch as the identical formation of the individual pipe straps assures that the load placed on the pipe will be equally distributed to each strap.
In certain instances, a single structural channel may support a plurality of pipes in side by side, spaced fashion. An individual pipe clamp is used to secure each of the pipes to the structural channel. However, when the pipes are arranged in such close side by side fashion, it is often difficult to access the bolt extending through the connection ends of the straps to tighten the pipe clamp. Positioning of one clamp immediately next to another clamp hinders access to the bolt making installation difficult.
In order to permit access to the bolt which tightens the straps together, the art has seen an improvement in the conventional pipe clamps used in side by side arrangements. U.S. Pat. Nos. 4,757,965 and 5,163,644 each show pipe clamps having connection ends extending beyond the bolt. The connection ends are bent or twisted so as to be aligned at an angle with respect to the extending pipe. In these example the fastener or bolt is therefore inserted at an angle with respect to the pipe so that the head of the bolt is accessible for tightening even where pipe clamps are installed in a close side by side relationship.
While the arrangement shown in the above-referenced patents overcomes many of the disadvantages of prior pipe clamps, this arrangement requires the connection portions of the strap to be bent or twisted during manufacture. This may have a tendency to greatly reduce the strength of the pipe clamp, reducing the load which may be supported by the pipe.
A further technique to allow pipe clamps to be placed in close side by side relationship is shown in U.S. Pat. No. 5,141,186. In this example, the pipe clamp includes straps of unequal length so that the extending connection ends are located to one side and at an angle to the pipe extending across the structural channel. The threaded fastener is thereby centrally offset and extends at an angle with respect to the pipe in such a manner that the head of the bolt is directed upwardly with respect to the pipe rather than across the pipe. This allows access to the head of the bolt where the pipe clamps are placed in close side by side relationship. While this arrangement allows for tightening of the bolt of the pipe clamp where the pipes supports are in close proximity, the unequal nature of the pipe straps of this example result in stresses being unequally applied to the individual straps of the clamp. This also may result in the pipe being unable to support excessive loads.
Therefore it is desirable to provide an improved pipe clamp which securely supports the pipe to a structural channel and which may be easily accessed where the pipes are arranged in close proximity.